Worm-wheel generator or milling-machine.



P. BROWN & P. J. BOSTOGK. WORM WHEEL GENERATOR OR MILLING MACHINE.

APPLICATION FILED OGT.8, 191 3.

1,1 22,068. Patented Dec. 22, 1914.

4 SHEETSSHEET l.

P. BROWN & F. J. 'BOSTOOK. WORM WHEEL GENERATOR OR MILLING MACHINE.APPLICATIQN FILED 00T.8, 1913.

1, 1 22,068. Patented Dec. 22, 1914.

4 SHEETS-SHEET 2.

' .'1 :.;BR0'WN & P. I. BOSTOGK. ww. WORM WHEEL GENERATOR OR MILLINGMACHINE.

i v APPLIGATIYON FILED 00T .8, 1913.

1 1 22,068. Patented Dec. 22,1914.

4 SHEETS-SHEET 3.

. P. IBR0W1\T&F. J. BOSTOGK. WORM WHEEL GENERATORVOR MILLING MACHINE.

APPLIO ATION FILED 00128, 1913.

Patented Dec. 22,1915

4 SHEETS-SHEET 4.

in it Malia in willit: n

i XVORIEJNHEEL (RENEE 'C'R CB. llIiLLINCT-;ACHII?E.

Application filed October S, 1313.

To (ZZZ 2071 m it may concern Be it known that we, PERCY BROWN andFRANCIS JOHN Bosrocn. subjects of King George V of Great Britain,residing at Huddersfield, in the county of York England, have inventedcertain new-and useful Improvements in ll orm-llheel Generators orMilling-lviachines, of which the following is a specification.

This invention has reference to worm Wheel generating or like millingmachines, and comprises an improved construction or arrangement of thecutter carrying head which is specially intended to take all the lateralstrains or stresses set up during the cutting" or generating operationand eliminate overhang of the parts, the said head containing the wholeof the mechanism for driving the cutting hob and enabling the hob to befed either directly into the worm Wheel or like blank or tanfzjcntiallyto it.

The invention will described with reference to the accompanyingdrawings, in which Figure 1 is a. front elevation of a worm wheelgenerating niachine having the improvemcnts applied thereto; 2 is a planview of the machine; Fig. 3 is a side cleration of the machine, lookingin the direc tion of the arrow A, Fig. '2, and l is a side elevation,partly in section. looking in the direction of the arrow B, Fig.

According to our invention we employ a cutter head 1 slidahle on ways onthe machine frame 9 toward or away from the rotatable work table 3carrying the spindle 4 on which the worm wheel or like hlank'to he cutis secured. The portion or face 5 of the head on which the slide 6carrying: the hob spindle 7 is mounted. is made to incline, as is shownclearly in Figs. 3 and i from its lower edge outwardly or forwardly at asuitable angle to the vertical axis of the work spindle 4, the angleused being approximately that of 45 though this may be varied somewhateither way without detriment. The guide surface of the. frame ishoriaontal when the spindle at is vertical, and the guide face 5 of thehead is arranged at an acute au lo to and suhtending. or exhoh slide heverti- Spcciacation of Letters Eetent.

Patented Rec. 22,

Serial Etc. 794,044.

the work which is so common on other worm wheel ieratingi machines. Atthe same time ovcri'iang of the support for the hob spindle eliminated.and we are enabled to out very small wheel.

The machine is driven from a single pulley S by means of a frictionclutch 9 operated hy a hand lever 10 fast on the end of rod 11 extendingto the far side of the machine. Motion is transmitted from the pulley 8through a suitable chance speed gear box 19 to a horizontal shaft 13which, through suitable gears or dividing change wheels H 3 es motion toa shaft 15 from which the work table is driven by worm and wormwheel,not'shown. The change speed gear 19 is controlled by a hand wheel 16"fast on the end or" a rod 17 extending to tile for side of the machine.The shaft has akeyway 18 in which is slidable a key 19 carried by abevel wheel 90 supported in a bearing n a bracket 21 carried by thehead 1. The head 1 is slidable toward or away from the work table bymeans of a feed screw'22 (Fig. 3) passing through a denendin r nut 93 onthe head. the screw 2-2 carrying a bevel wheel 24 meshing with he'elwheel (Fig. 2) fast on a shaft 26 .ch extends to the same side of themachine as the rods 1'1 and 17, and provided with an operating handwheel 2?.

The head 1 carries all the mechanism, for rotating and traversing thehob cutter. and the motion for driving such mechanism is transmittedthrough the bevel which slides to and fro on the main shaft the head ismo ed toward or away from the work ahle according to the diameter of theblank being out. A short diagonal shaft '29 supported by the bracket 21has fast on its lower end a bevel wheel 30 which meshes with the bevelwheel 20 and this shaft *3) drives both the hob rotating mechanism andthe hoh slide traversing mechanism. The rotation of the hob is effectedthrough a diii orcntial motion or compensating gear 28 at the upper endof the shaft '29 which ditt'erential motion drives a short diagonalshaft having: fast thereon a worm 32 mesh ng with a worm wheel sliilahlykeyed on the hoh spindle 7. The short-diagonal shaft 31 an extension ofthe interiitc dri ing shatt if. being: a Tet-(l y in line with an remixto t the compcnsatio extension shaft 31 is connected positively with thehob spindle 7. l The directness of the drive from the shaft 13 to thehob spindle which will best be understood by an examination of Fig. l,obviates the use of the long shafts or driving connections between suchparts,

the importance and advantage of which will be readily appreciated bythose skilled in i motion 28 is a worm 34 Which meshes with a worm wheel35 fast on a transverse shaft 36. This transverse shaft drives, througha- 1; suitable change speed gear 37, a hollow transverse shaft 38, faston which is a worm 39 meshing with a worm wheel 40 fast on a short shaftll, which is supported in a suitable bearing 42, and has fast upon itsfront :0 end a bevel wheel 43. A feed screw'l l,

passing through a nut on the slide 6, carries a, sliding clutch 46rotatively connected to it, and two loosely rotatable bevels 4:7 and i8meshing with the bevel 43. Movement of the clutch 46 into drivingengagement with one or other of the bevels 47 or 48 which rotate inopposite directions, will cause the screw it to be rotated in onedirection or the other whereby the slide 6 can be trav- 30 erscd ineither direction according as the hob cutter employed be a-right hand ora left hand cutter. Suitable automatic trip gear is provided todisengage the clutch at the end. of movement of the slide in eitherdirection. Any approved trip gear can be used, and the trip gear showncomprises lugs on the slide 6, as shown in Fig. 1, adapted to come incontact with a collar 61 on arod 62 which is slidable longitudinally 40me bearing 63 on the head 1. The rod 62, as shown in Fig. 3, isoperatively connected with a lever 64 secured on a rock-shaft 65 whichis carried by the head. The lower end of the rock-shaft 65 has a lever66 secured on' it, and the free end of the lever 66 engages with acircumferential groove in the clutch 46, see Fig. 2, which clutch issplined on the feed screw 44 shown in Figs. 2 and 3. The rate oftraverse of the slide is determined by the change speed gear 37, whichmay be of any suitable construction to give the desired range of speeds,and is controlled by a hand wheel 4-9 located on the same side of themachine as the hand Wheels l6 and 27 and hand lever 10. The hand wheel49' is suitably graduated to show the feed per revolution of the hob.

To provide for variation of the speed of.

rotation of the hob relatively to the rate of 59 feed of the slide 6 bywhich the hob is traversed the feed screw 44: is connected by changegearing 50 with a transverse shaft 51 passing through the hollow shaft3. said shaft having fast on its opposite end a worm the angle of whichis such that the worm 52 nieshes with a worm'wheel 53 integral with orsecured to the casing of the differential motion 2S ,and by varying thespeed of rotation of said casing the rotary employed asecondintermediate wheel would be provided in' the change gearing 50inorder to preserve the proper direction of rotation of theshaft 51.Disengagement of the clutch 46 at the end of movement of the slide 6 ineither direction, that is to say on completion of a cut,- stops the feedand also stops thedifferential action of the motion 28, as will beunderstood. When a cut has been completed, that is to say, when the tripmotion has brought about disengagement of the clutch 4-6, the machine isstopped and the feed screw 4.4 is rotated by. hand, by means of ahandleapplied to the squared end 5% of the screw, to reverse themovement of the slide 6 and carry the hob back to the commencingposition. Through the change gears 50, shaft 51, worm 52 and worm wheel53, the differential motion is simultaneously operated to cause the hobto speed of the hob is varied as will be under- .7 stood. In the eventof a left hand hob being be rotated as it is moved back, thc. remainderof the mechanism meanwhile remaining stationary. The speed of rotationof the hob as it is moved back is determined by the change gears 50. Bythe means described, the position of the hob relative to the work can beset up by hand, thereby re lieving the operator of the considerablelabor involved in rotating the work table to set up the hob to the workas is usual. It will be observed that the whole of. the hob operatingmechanismjs carried by the cutter head and moves therewith as the headis fed toward or away from the work table; the drive for rtfiating thehob is as direct as possible; diiferntiation for lead is on to the hobdrive and not on to the Work; the hob slide can be moved, and the hobrotated, by hand without affecting the remainder of the machine, Whilethe control of the mechanism is so arranged as to be within easy reachof the operator when standing in the best position for viewing thecutting of the wheel.

The details of construction shown may be varied without departing fromthe invention within the scope of the appended claims.

Having thus described our invention, what we claim as new and desire tosecure by Letters Patent is:

1. In a milling machine, the combination,

with a supporting frame, and a work spind e carried thereby; of a headcarried by the frame and arranged adjacent to the work spindle andprovided with a guide face arranged in an upwardly and forwardly 111--clined position with respect to the work a feed screw engaging withspindle, and hob slide carried by the head and vvorking against itsinclined guide face.

2. in a milling machine, the combination, with a supporting frameprovided with a guide surface, of a head slidable on the said guidesurface and provided with a guide face arranged at an acute angle to andsubtending the said guide surface, and a hob slide carried by the headand workingagainst its inclined guide face.

In a milling machine, the combination, with a supporting frame, a headslidable on the frame, and a hob slide slidable in the said head; of anut secured to the hob slide,

the nut and carried by the head, an intermediate driving shaft carriedby the head, driving mechanism connecting the intermediate driving shaftwith the feed screw, a main driving shaft carried by the said frame, anddrivingmechanism slidable longitudinally of the main driving shaft andoperatively connecting it with the intermediate driving shaft.

at. In a milling machine, the combination, with a supporting frame, ahead slidable on the frame, and a hob slide slidable in the said head;of an intermediate driving shaft carried by the head, a main drivingshaft carried by the said frame, driving mechanism slidahlelongitudinally of the main drivinshaft and operatively connecting itwith toe intermediate driving shaft, a hob spindle glonrnaied in the hobslide, and intermediate driving mechanism operatively connecting hobspindle with the said intermediate driving shaft.

5. in a milling machine, the combination, with a head, and a hob slideslidable in the head; of an intermediate driving shaft carried by thehead, an extension shaft arranged in line with the said shaft and .alsocarried by the head, eratively connecting spindle journaled in devicesoperating to revolve the hob the two shafts, a hob spindle from the saidextension shalt, traverse the hob spindle relatively to the speed oftraverse of the hob slide.

6. In a milling machine, the combination, with a head, a h'ob slideslidable in the head, and a hob spindle journaled in the hobslide-g of adriving shaft formed in two sections, compensating gear operativelyconnecting the said sections, traversing mechanism, for sliding the hobslide, operatively connected to one shaft section, driving devicesoperating to revolve the hob spindle from the other shaft section, anddriving connections provided with change gearingand operativelyconnecting the said traverse mechanism with the said compensating gearand operating to vary the speed of rotation of the hob spindlerelatively to the speed of traverse of the hob slide.

In testimony whereof We aiiix our signa tures in the presence of twoWitnesses.

PERCY BROWN. FRANCIS JOHN BOSTGCK.

Witnesses:

W. WHITELEY, C. E. Hmcnrrrr.

compensating gear opthe hob slide, driving I

